Device for shielding ground workings with means for controlling the dust

ABSTRACT

A device for reducing dust in workings such as underground workings which are supported by shields comprises a plurality of shields each having a top and a side wall on at least one side disposed alongside and spaced from the next adjacent shield side wall. A liquid conduit is carried by the sheild adjacent the top of its side wall and it is provided with a plurality of openings or discharge nozzles along its length in order to direct a dust settling liquid or spray downwardly adjacent the side wall. An elastic seal extends outwardly from the bottom of the side wall and applies against a similar seal of the next adjacent shield. The two shields together define a runoff gutter for the liquid employed to settle the dust.

United States Patent [191 Koppers 1 Sept. 23, 1975 [54] DEVICE FOR SHIELDING GROUND 2963,284 l2/l960 Bradford 261/117 ggfiggfifi ggg g FOR FOREIGN PATENTS OR APPLICATIONS E UST l,95l,l 17 4/197] Germany 98/50 Inventor: Manfred Koppers, Duisburg,

Germany Assignee: Rheinstahl AG, Germany Filed: Oct. 24, 1974 Appl. No.: 517,592

Foreign Application Priority Data Nov. 17. 1973 Germany 2357533 Primary ExaminerBernard Nozick Attorney, Agent, or FirmMcGlew and Tuttle [5 7] ABSTRACT A device for reducing dust in workings such as underground workings which are supported by shields comprises a plurality of shields each having a top and a side wall on at least one side disposed alongside and spaced from the next adjacent shield side wall. A liquid conduit is carried by the sheild adjacent the top of its side wall and it is provided with a plurality of openings or discharge nozzles along its length in order to direct a dust settling liquid or spray downwardly adjacent the side wall. An elastic seal extends outwardly from the bottom of the side wall and applies against a similar seal of the next adjacent shield. The two shields together define a runoff gutter for the liquid employed to settle the dust.

8 Claims, 7 Drawing Figures US Patent Sept. 23,1975 Sheet 1 of2 3,906,733

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DEVICE FOR SHIELDING GROUND WORKINGS WITH MEANS FOR CONTROLLING THE DUST BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates in general to the construction of shields and in particular to a new and useful device for shielding ground workings or underground workings which includes a plurality of shields arranged in spaced side by side relationship with side walls having an outwardly extending seal adjacent the lower end thereof and carrying a conduit it its top which sprays liquid in the space between the shields in order to settle the dust therebetween and to cause it to run off along the seals.

2. Description of the Prior Art The present invention has particular application for underground workings particularly in coal mines where shield supports are required. While using a shield support the free face between the hanging wall, the footwall, the coal face and the workedout area is smaller than in a Iongwall. Since the air volume required for the workings is independent of the cross section of the operational space, the air velocity in the shield supported workings is higher than in a longwall. For this reason it is difficult to control the dust in said shield supported workings.

It is well known to trap the dust in the space between the hanging wall plate and the shield by injecting water through nozzles into the space and to drain off the mud thus produced. However, within a short time the nozzles become clogged by stone particles which break away and thus and thus it becomes inoperative.

Attempts have also been made to keep the dust away from the space between the shields by various shaping of the upper ends of the lateral shield plates in a con struction in which the dust is permitted to slide by its own weight down the back of the shield toward the worked-out area. In such cases a portion of the dust is kept away from the working face but a trapping of the dust is not obtained.

SUMMARY OF THE INVENTION In accordance with the invention there is provided a shield device in which the dust is trapped directly at the location of its occurrence and it is drained away as mud. In contrast to the prior art constructions this draining is provided through the gap between two adjacent shields and the mud is evacuated to a place which is not required for the conveying and for the working mechanisms.

In accordance with the invention at least one side of the shield carries a liquid conduit adjacent the upper edge thereof which extends along substantially the entire length of the shield and is provided with openings for the liquid which are turned to direct a liquid spray or stream on at least one side of the shield so that it is directed preferably along the lower edge of the side plate. An elastic seal is mounted to project outwardly from the bottom of the side plate and it is formed with a U-shaped configuration having a central portion which projects against a similar seal carried on the next adjacent plate so as to form a runoff gutter on the tops of the seals which extend along the bottom edge of the plate.

In accordance with the invention the elastic sealing preferably has a substantially U-shaped cross section and it includes legs of unequal length with the longer leg being secured to the underside or adjacent the lower edge of the side wall of the shield. The sealing is advantageously connected to the shield by resilient members. In order to keep the space below the shield in the zone between the two shield units free from mud also during the advance, the invention provides that the distance between the outer edge of the elastic sealing and the plate is larger than the maximum possible distance between the side plates of two adjacent shield units. The liquid conduit for the shield may be designed as a pipe which is welded to the shield and thus it serves also as a bearing member. Such a pipe may be entirely or partly formed by the structural elements of the shield or a separate liquid conduit is mounted separately on the shield or at a spaced location therefrom or connected thereto by a resilient support member.

Accordingly it is an object of the invention to provide an improved shield for underground workings which includes a top wall and a side wall with a conduit for liquid extending along the top of the side wall and having openings directed downwardly into the space between the side wall and the side wall of the next adjacent shield and wherein the shield is provided with a lower edge having an outwardly extending sealing member which engages against the sealing member of the next adjacent shield so as to form a runoff gutter therewith extending along the length of the shield adjacent the bottom edge of the side wall.

A further object of the invention is to provide a shield construction which is simple in design, rugged in construction and economical to manufacture.

For an understanding of the principles of the invention, reference is made to the following description of typical embodiments thereof as illustrated in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the Drawings:

FIG. 1 is a side elevational view of a shield constructed in accordance with the invention;

FIG. 2 is a sectional view of the shield taken along the line IIII of FIG. 1;

FIG. 3 is an enlarged partial sectional view showing the lower edge of a shield side plate wall;

FIG. 4 is a view similar to FIG. 3 showing a pair of shields placed in side by side relationship;

FIG. 5 is a view similar to FIG. 4 showing an offset ting of one shield in respect to the other;

FIG. 6 is an enlarged sectional view of an upper edge of a shield showing another embodiment of conduit construction; and

FIG. 7 is a partial sectional view similar to FIG. 2 of the upper corner of the shield of another embodiment of the invention.

GENERAL DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings in particular the invention embodied therein in FIGS. 1 to 5 comprises a shield generally designated 1 which is adapted to be used in underground coal mining operations and which includes an upper end la which is adapted to be secured on a pivot element 50 which is secured for example on a structure such as a support beam 52.

In accordance with the invention the shield l includes at least a portion of generally rectangular configuration with a top wall 2 and side walls 54 and 56 which extend downwardly from each side of the top wall 2. A liquid conduit designed as a pipe 3 is welded to the shield adjacent the juncture between the top wall 2 and the side walls 54 and 56 and it extends along a substantial length of the respective side walls. The pipe is provided with openings 4 which are oriented to direct liquid downwardly in a stream or spray exterior of the associated side walls 54 or 56 and between the side walls of adjacent shields l and 1'.

In accordance with a feature of the construction elastic sealings or seal members 5 are secured to the lower end of each side wall 54 and 56 for example to bottom plates 8 which extend substantially parallel to the top walls 2. Each seal member 5 has a substantially U- shaped cross section which includes a longer leg 7 which is secured to the bottom plate 8 and a shorter leg 70 which extends outwardly from the plate. As shown in FIG. 3 the seal 5 includes a rounded top or intermediate portion 6 which is adapted to be positioned against the next adjacent side wall 54 or 56 of the next adjacent shield 1' with sufficient pressure so as to flatten it against the associated wall as shown in the arrangement of FIG. 5 or to flatten it against the associated sealing member 5' of the next adjacent shield l as shown in FIG. 4. Each shield 5 or 5 is advantageously secured in position by a Clamping plate 58 which may be bolted to the bottom plate 8. The distance a from the outer surface of the side plate 56 to the apex of the intermediate portion 6 is larger than the largest possible distance b between two adjacent side plates as shown in FIGS. 3 and 4 respectively. The dust 60 shown in FIG. 4 in the interspace between the plates 56 and S4 of adjacent shields l and l is trapped by the water jets or streams discharged through the openings 4 of the pipes 3 and that the dust becomes entrained downwardly in the liquid which is subsequently drained by running off along the top surfaces of the seal members 5.

The arrangement of FIG. 4 shows an arrangement where adjacent shields operate on substantially the same level and are not offset during the time in which they are guided along the working face. In such a condition the seal members 5 and 5' bear against each other and the top surfaces thereof form a runoff gutter for the dust and liquid slurry. When the shields are moved so that they are offset vertically as shown in H6. 5 the dust 60 collects only about the seal member 5 which bears against the plate 54'.

In the embodiment shown in FIG. 6 a shield generally designated 1" includes a top wall 10 and a side wall 62. A plate member 11 is welded to each of the plates 10 and 62 and forms a conduit or passage 31 for liquid which may be discharged through one or more openings 41 defined along the side wall 62. In the embodiment shown in FIG. 7 a shield generally designated 1 includes a top wall 70 and a side wall 21 which are spaced inwardly from respective top plates 72 and side wall plates 74 which are mounted by one or more resilient mountings 9 on the shield 1'. A liquid conduit 32 is carried by the plates 72 and 74 so that it is at a spaced location outwardly from the wall 21 of the shield. Resilient mountings 9 a first spring cylinder 90 on the plate 21 and a second spring cylinder 9b on a plate 74. Spring means such as a coil spring 34 is arranged within the cylinders and 9b and keeps the plate 74 at a desired spacing. This embodiment is particularly advantageous in cases where larger distances must be provided between the field units during the advance.

While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

l. A device for reducing dust in workings such as underground coal mines wherein the walls are supported by shields, comprising a shield having a top and a side wall on at least one side, a liquid conduit carried by said shield adjacent the top of its side wall and connected to a liquid supply and having a plurality of openings for the liquid along its length oriented to discharge liquid downwardly adjacent said side wall, and an elastic seal member extending outwardly from the bottom of said side wall and defining a runoff gutter for the liquid and entrained dust extending along said wall.

2. A device according to claim I, wherein said seal member has a substantially U-shaped cross section and includes a long leg portion connected to the lower end of said side wall, an intermediate web portion and a short leg portion spaced outwardly from the bottom of said short leg portion.

3. A device according to claim 1, wherein said shield includes a bottom wall extending inwardly from said side wall and elastic means securing said seal member to said bottom wall.

4. A device for reducing dust in workings which are supported by shields, comprising a plurality of shields each having a top wall and a side wall on at least one side of said top wall, a liquid conduit extending along said side wall adjacent the top thereof and connected to a liquid supply and having a plurality of openings for the discharge of the liquid along its length oriented to discharge liquid downwardly adjacent said side wall, and an elastic seal member extending outwardly from the bottom of and along said side wall and applying against the next adjacent shield and defining a runoff gutter for the liquid between said shields, said seal member comprisi-ng a U-shaped member having a first leg portion connected to the bottom of said shield, an intermediate portion and a second leg portion spaced outwardly from said first leg portion, said intermediate portion extending outwardly beyond the edge of said side wall by a distance which is greater than the distance between adjacent side walls of said adjacent shields.

5. A device according to claim 4, wherein said liquid conduit comprises a pipe firmly secured to said shield.

6. A device according to claim 4, wherein said liquid conduit is formed of structural elements of said shield.

7. A device according to claim 4, including a resilient mounting supporting said liquid conduit on said shield.

8. A device according to claim 4, including a bottom plate secured to the lower end of said side wall, said sealing member being clamped to said bottom plate,

said shield having a side wall on each side. 

1. A device for reducing dust in workings such as underground coal mines wherein the walls are supported by shields, comprising a shield having a top and a side wall on at least one side, a liquid conDuit carried by said shield adjacent the top of its side wall and connected to a liquid supply and having a plurality of openings for the liquid along its length oriented to discharge liquid downwardly adjacent said side wall, and an elastic seal member extending outwardly from the bottom of said side wall and defining a runoff gutter for the liquid and entrained dust extending along said wall.
 2. A device according to claim 1, wherein said seal member has a substantially U-shaped cross section and includes a long leg portion connected to the lower end of said side wall, an intermediate web portion and a short leg portion spaced outwardly from the bottom of said short leg portion.
 3. A device according to claim 1, wherein said shield includes a bottom wall extending inwardly from said side wall and elastic means securing said seal member to said bottom wall.
 4. A device for reducing dust in workings which are supported by shields, comprising a plurality of shields each having a top wall and a side wall on at least one side of said top wall, a liquid conduit extending along said side wall adjacent the top thereof and connected to a liquid supply and having a plurality of openings for the discharge of the liquid along its length oriented to discharge liquid downwardly adjacent said side wall, and an elastic seal member extending outwardly from the bottom of and along said side wall and applying against the next adjacent shield and defining a runoff gutter for the liquid between said shields, said seal member comprisi-ng a U-shaped member having a first leg portion connected to the bottom of said shield, an intermediate portion and a second leg portion spaced outwardly from said first leg portion, said intermediate portion extending outwardly beyond the edge of said side wall by a distance which is greater than the distance between adjacent side walls of said adjacent shields.
 5. A device according to claim 4, wherein said liquid conduit comprises a pipe firmly secured to said shield.
 6. A device according to claim 4, wherein said liquid conduit is formed of structural elements of said shield.
 7. A device according to claim 4, including a resilient mounting supporting said liquid conduit on said shield.
 8. A device according to claim 4, including a bottom plate secured to the lower end of said side wall, said sealing member being clamped to said bottom plate, said shield having a side wall on each side. 